1. Field of the Invention
The present invention relates to an electronic musical instrument which is effectively applied to electronic stringed instruments such as, for example, an electronic guitar, electronic violin, guitar synthesizer, and the like. More particularly, it relates to an electronic musical instrument having a fret-split function which is capable of assigning specific tone colors to fingering areas, respectively, divided on the basis of frets as boundaries.
2. Description of the Related Art
In the field of electronic stringed instruments, electronic stringed instruments with a string-split function are well known in the art. In this type of electronic stringed instruments, a specific tone color is previously assigned to each string or to a plurality of strings, and when a certain string is plucked, musical tones are generated in response to plucking operation, which have the tone color assigned to the plucked string. With use of these electronic stringed instruments, in which different tone colors are assigned to respective strings from the first string to the sixth string, musical tones each having a different tone color can be successively generated by plucking the strings successively in order from the first string to the sixth string.
In these electronic stringed instruments, however, a specific tone color is assigned to each string or to particular strings. Therefore, when a musician plays the instrument with a stroke-performance, or when the musician rapidly plucks the strings in order from the first string to the sixth string or reversely in order from the sixth string to the first string, strings shall generate musical tones each having a tone color assigned to the corresponding string or assigned to particular strings. Accordingly, when the musician plucks a plurality of strings at the same time or sequentially to execute a chord-performance, musical tones shall be generated, which have different tone colors which correspond to tone pitches composing the chord. As a result, a problem remains that musically unfavourable musical tones are generated.
Meanwhile, some electronic keyboard musical instruments with a key-split function are well known, in which keys on the keyboard are divided into two groups such as a lower tone-pitch key group and a higher tone-pitch key group on the basis of a key representing a particular tone pitch, and different tone colors are assigned to these key groups, respectively, and thereby keys belonging to these lower and higher tone-pitch key groups generate musical tones having different tone colors, respectively.
However, it is difficult to apply the technique relating to such a key-split function without any modification to electronic stringed instruments. More specifically, in a conventional stringed instrument, a group of musical scales assigned to each string are differently arranged on a finger-board. For example, in a six-string guitar, a tone pitch assigned to an open-string fret position of the first string is the tone pitch E.sub.4, a tone pitch assigned to the same position of the second string is the tone pitch B.sub.3, a tone pitch assigned to the same position of the third string is the tone pitch G.sub.3, a tone pitch assigned to the same position of the fourth string is the tone pitch D.sub.3, a tone pitch assigned to the same position of the fifth string is the tone pitch A.sub.2 and a tone pitch assigned to the same position of the sixth string is the tone pitch E.sub.2. A group of musical scales are assigned to respective frets of each string on the basis of the above tone pitches, E.sub.4, B.sub.3, G.sub.3, D.sub.3, A.sub. 2 and E.sub.2. Accordingly, there shall be assigned a plurality of same tone pitches (for example, the tone pitch C.sub.4) within a specific fingering area, or within, for example, a specific fingering area confined between the first fret position and the seventh fret position. Therefore, if a split position, on the basis of which tone colors are assigned is set to a specific tone pitch position, for example, the position of the tone pitch D.sub.4, and if different tone colors are assigned to frets located within a higher tone-pitch area and a lower tone-pitch area, which are divided by the above position of the tone pitch D.sub.4, then different tone colors shall be assigned to the position of the tone pitch C.sub.4 and to the positions of the tone pitches E.sub.4, G.sub.4, respectively. As a result, such a problem will arise that when the musician stops strings within a relatively narrow fingering area between the first fret and the seventh fret to play C major chord, the C major chord composed of tone-pitches C.sub.4, E.sub.4 and G.sub.4 can not be produced with the same tone color.